Sand drier



B. R. SMITH Dec. 26, 1950 SAND DRIER Filed Aug. 1, 1949 INVENTOR. Sz/F020 2. SMIT/1,

TTOA/EYS.

Pstenteg-Dee. 26, 19,50, e,

UNITED SAND mmm e Buford B. Smith, Mishawaka, Ind. Application August 1, 1949, Serial No. 107,942

This invention relates to improvements in sand driers, and more particularly to a device by means of which excess moisture can be removed from sand.

, i The primary object of the invention is to pro-l vide a novel and simple device for drying sand, provided with automatic means to controlthe feeding of damp sand to a drying element and to control the temperature of the drying unit.

A further object is to provide a sand drier with a feed hopper mountingA a vibrator whose rate of operation is responsive to a switch having a shiftable actuator located at the` discharge outlet of the hopper to be shifted between two operative positions depending on the rate of discharge of sand from the hopper.`

A further object is to provide a drier of this character having a drying chamber carrying electrical heating elements, a thermostatic switch controlling said elements and located adjacent the upper end of said chamber, and baiiles at its lower end for retarding flow of moist sand but permitting the ready discharge of dry sand.

A further object is to provide a sand drier comprising a feed hopper positioned above and discharging into a heating chamber, said lhopper being spaced from the walls at the top of said chamber to accommodate a shiftable switch actuator having a portion located adjacent to the outlet of the hopper to be actuated by sand discharged from the hopper.

Other objects will be apparent from the following specification.

In the drawing:

Fig. l is a fragmentary side view of the device.

Fig. 2 is a top plan view of the device.

4 Fig. 3 is a view of the frame, taken on line l-S of Fig. 1, with the hopper, heating chamber and controls removed.

Fig. 4 is an enlarged fragmentary detail side view of the device with parts shown in section, taken on line 4--4 of Fig. 2.

Fig. 5 is a wiring diagram of the device.

Referring to the drawing which illustrates the preferred embodiment of the invention, the numeral I 0 designates a container for sand or like material, into which is to be discharged sand dried in a heating chamber I2 to which sand has been fed by a hopper i4, said hopper and chamber being supported by a frame unit I6.

The frame I6 preferably constitutes a plurality of uprights or leg portions I8 which have ilxedly connected thereto an upper set Aof connecting plates 28 and a lower framework, including the bars or angie irons 22, beat seen in Fig. 3. The

1o claim. (c1. 34-44) parts may be bolted, pivoted, welded or otherwise secured to form a strong, solid or sturdy rein-V forced frame. The lower frame members 22 are preferably spanned or reinforcedby a pair of spaced cross-braces 24. The U-shaped plate 26 V having parallel arms 28 is ilxedly,l secured upon l the cross-bars 24 so that the opening within the U is positioned substantially centrally of the frame. i

A feed hopper, preferably having `an upper cylindrical portion .36 and a` frusto-conical or tapered lower portion 32, is supported `by t e upper part of the frame. As here illustrated, t e upper cylindrical frame part is xedly secured to the upper 'frame members 20 by bolts 4or other securing members 24 at spaced points. The lower end or discharge outlet of the tapered part 32 of the hopper preferably terminates at or adjacent to the level of the U-shaped plate 26 as best seen in Fig. 4. The hopper mountsa vibrator 36 of any suitable type upon the exterior' thereof, preferably at its` tapered portion 32 and adjacent its lower `or discharge end, as best seen in Fig.` 1. This vibrator is preferably housed within a casing having flanges or other parts, by means of which the vibrator may be secured to the hopper, as illustrated at 38. n

The heating chamber I2 preferably constitutes a housing 40, open at its top and its bottom ends, and here illustrated as tapering slightly lengthwise thereof so that its upper portion is of larger cross-sectional size than its lower portion. The upper portion of the housing 40 is preferably provided with an outwardly flared or tapering marginal flange 42 `whose small dimension portion is `end is preferably of a slightly larger size than the inner dimension of the U-shaped member 26, 28. Consequently, the chamber 40 can'be inserted within and suspended from the member 26,

26 with the flange 42 bearing upon said U-shaped member 26, 28 at three sides thereof. The fourth side of the chamber 40 preferably has a laterally projecting substantially horizontal lip 44. of retainers 46, each preferably having a nger portion 48, is carried by the frame, as at the members 24 thereof at the ends of the parallel arms 28 of the U-shaped support 26, 28. The fingers preferably project inwardly beyondthe inner edges of the arms 28 underlying portions of the ange 42 and forming `barriers to prevent removal of thecasing 40 from the U-shaped member 26, 28 by horizontal sliding thereof through the mouth of said U-shaped member 26, 28.

A pair` Upward displacement or release of the chamber 40 from the supporting U-shaped frame member 28, 28 is prevented by one or more latch members 50 secured to the mounting unit 28, 28 and having lip portions 52 projecting inwardly from said member 26, 28 and adapted to bear upon the upper edge of the tapered flange 42 of the chamber 40. The inner dimension of the chamber 40 as its upper end is preferably substantially greater than the outer dimension of the hopper portion 32 at its discharge outlet so that, when the hopper I4 is substantially centered relative to the drying chamber I2, a substantial clearance space extending entirely around the hopper, as seen in Fig. 4, will be provided. In the preferred form as also illustrated in Fig. 4, the hopper will terminate at substantially the level of the flange 42, although it may terminate above the level of the chamber I2, if desired.

A plurality of heating elements 04, here shown as elongated strip electric resistance members, are mounted upon the outer surface of the chamber 40, the number of such heater elements depending upon the rate of heat generation desired, it being understood that one heater element may be sumcient or that a number of such heating elements may be required or advantageous. The heating elements are preferably encased within a sheath 56 encircling the housing 40, from which sheath project terminal strips 58, each carrying a terminal post 60. ably connected in parallel to be controlled by a temperature responsive switch 62, here shown as carried by the flange 44 in depending relation thereto at the upper end of thechamber 40. The switch may be of any suitable type responding to temperature, i. e., having a thermostatic actuator.

Two or more baille plates 64 are carried by the chamber 40 at the lower end thereof, said bale plates preferably being flanged at 66 for anchorage with the chamber 40, as by means of bolts or rivets. The bailies 64 are located at different levels spaced apart a small distance, and each thereof is of a size greater than one-half of the cross-sectional size of the chamber 40 at the level at which the baille is located. The baiiies are secured to opposed side portions of the chamber 40 and their inner end portions or margins overlap, as shown in Fig. 4. The baiiles 64 preferably are tilted downwardly a few degrees from horizontal from their anchored end toward their free or inner edge.

'I'he U-shaped member 26 preferably mounts a pair of brackets to which is pivoted at 12 a.V

grille, including a plurality of elongated wires 'I4 and a cross-wire 16 interconnecting said wires 14. The intermediate portion I8 of the wires 14 is preferably ofi-set, as best seen in Fig. 4, so as to permit the grille 14--18 to pass downwardly through the mouth at the upper end of the chamber 40 to a position clear of and extending below the major portion of the discharge outlet of the hopper 32. A bracket 80 is xedly secured upon the members 26 adjacent to the bracket 10 and carries a switch 82, such as a micro switch having a feeler element which is adapted to be actuated by a lever portion 84 of lthe pivoted grille 14-18. 'I'he switch 82 is adapted to be interposed in the circuit leading to the vibrator 36.

An illustrative circuit of this type is illustrated in Fig. 5, wherein a pair of alternating current leads 90 have connected thereacross leads 92 with which the heating elements 54 are connected in parallel, being suitably protected, as by heat re- The heater elements are prefersponsive fuses 84. Branch leads 8l are connected to the leads 92 to form a secondary circuit tothe vibrator 86 which ls parallel to the heater circuit. A suitable rectifier 98 and a control rheostat |88 are interposed in this branch circuit, the rheostat |00 being under the 1control of the switch l2 so that when the switch 82 is closed, a part of the rheostat resistance is shunted, causing the vibrator 88 to actuate at maximum amplitude. It will be apparent, however, that when the switch 42 is open, the full resistance of the rheostat |08 is interposed in the line and thus reduces the amplitude of vibration of the vibrator 20. A lead |42 connects the leads and contains control switches, such as the thermostatic switch 42 and manually controlled switches |04 and |08 which may be, respectively, a push button stop switch and a push button start switch.

In the operation of the device, assuming that the hopper 30, 32 has been filled with wet sand and that the control circuit has been energized by closing of the manual control switch, such as the starting switch |06. the hopper will be caused to vibrate at a limited amplitude of vibration, suflicient normally, however, to cause sand to be discharged from the hopper into the heating or drying chamber I2. The arrangement is preferably such that the amplitude of vibration of the vibrator will be insufficient to cause chatter or noise or other objectionable conditions. As the sand is discharged from the hopper into the drying chamber, it strikes the grille 14--18, thereby to tilt the same and open the micro switch 82 to place in circuit the rheostat |48. As the sand falls by gravity into the chamber 44 in its wet condition, it is held therein by the bailies 84. The chamber I2 is heated by the heating elements 54, and-incident to such heating, vapor is generated which discharges from said chamber 40 at the upper end thereof through the clearance space between the anges 42 and the hopper 32. The vapor passes upwardly along the tapered portion of the hopper and thus serves to heat the hopper and to preheat the moist sand within the hopper. When the sand has had its excess moisture removed, it will flow freely from the chamber 40 into the receptacle I0 past the baffles 84.

It will be observed that the weight of the sand within the heate:` is always bearing upon the grid I4- 18. Consequently, the sand causes the grid 14--18 to hold the switch 82 open. However, if the same becomes clogged within the hopper so that it will not discharge. and a void occurs above the grid 14-10, the grid will pivot upwardly, for which purpose it may either be so balanced that its lever portion 84 normally swings away from the switch 82, or a spring may be employed to urge the grid to a positionwlth the lever 84 thereof clear of the switch. In either event, the occurrence of a void with insuillcient sand to depress the grid causes the micro switch to close to shunt out all or a part of the resistance of the rheostat and thereby cause an increase in the amplitude of vibration of the vibrator 36. The increased amplitude of vibration will be suiiicient to dislodge the sand which may have become stuck in the upper part of the hopper thereby again'discharging sand from the hopper, whereupon the grid is again swung to a position to open the switch 82 for return of control of the vibrator to operate at partial amplitude only. Thus it will be apparent that as long as any sand is contained within the hopper, that sand will automatically feed into the drier as required, and the device is prevented from clog-v ging.

In the event an insufiicient quantity of moist sand to be dried is contained within the chamber, or in the event the outlet of the chamber 40 becomes stopped for some reason, or if for any other reason the temperature of the chamber l While the device is primarily intended for the drying of sand, its use is not limited thereto. Thus any granular material, particularly material of small particle size having a tendency when moist to cake or cohere, may be :dried by the device. Also, while the preferred embodiment of the invention has been illustrated and i described herein, it will be understood that changes in the construction may be made within the scope of the appended claims without departing from the spirit of the invention.

I claim:

1. A sand drier comprising a support, a heated chamber carried by said support and open at its top and bottom, a `feed hopper carried by said support above said chamber to discharge therein, a Vvibrator carried by said hopper. a switch controlling said vibrator, and a shiftable switch actuator carried by said support and positioned below the discharge outlet of said hopper.

2. A sand drier as dened in claim l, wherein i increases above safe limits, the thermostat conthe outlet ofsaid hopper is smaller than and substantially centered with the upper end of said chamber.

3. A sand drier as defined in claim 1, whereinx said support includes a substantially U-shaped horizontal plate, said chamber-having an outwardly flaring upper marginal ,flange bearing on" said plate, and a releasable retainer located at the mouth of said plate. l

4. A sand drier as defined in claim 1, an electric heating element carried by the exterior o1' said chamber and a temperature responsive switch controlling said element and carried at. the upper end of said chamber.

5. A sand drier as dened in claim 1, and a pair of vertically spaced svbstantiallv horizontal bames spanning the major portion of said chamber at the lower end thereof and overlapping at their inner margins.

6. A drier comprising a support, an open ended substantially upright chamber carried by said support, baflies within said chamber, means for neating said chamber, a feed hopper carried by said support and discharging into said chamber, said hopper having a tapered lower discharge portion located adjacent the upper part of said chamber and of smaller cross-sectional size than the adjacent portion of said chamber, an electric vibrator carried by said hopper, and means for controlling the amplitude of vibrations of said vibrator in response to the rate of discharge from said hopper.

7. A drier comprising a support. an open ended substantially upright chamber carried by said support. baffles within said chamber, means for' heating said chamber, a feed hopper carried by said support and discharging intosaid chamber, said hopper having a tapered lower discharge portion located adjacent the upper part of said chamber and of smaller cross-sectional size than the adjacent portion of said chamber, an electric vibrator carried by said hopper, a, controller for said vibrator carried by said support, and an actuator for said controller shiftable on said support and extending between said chamber and hopper to be positioned in the path of material discharged by gravity from said hopper.

8. A drier comprising a support, an open ended substantially upright chamber carried by said support, baflles within said chamber, means for 5 heating said chamber, a feed hopper carried by said support and discharging into said chamber, said hopper having a tapered lower discharge portion located adjacent the upper part'of said chamber and of smaller cross-sectional .size than the adjacent portion of said chamber, a grid pivoted to said support and including a portion extending transversely of and below the outlet of said hopper, a switch carried by said support and actuable by said grid, and a'vibrator carried by said hopper and controlled by said switch.

9. A drier comprising a feed hopper having a discharge outlet at its lower end, a heating chamber below said hopper and open at its top and bottom, baflles within said chamber, an electrically actuated vibrator, a control circuit including a rheostat controlling said vibrator and a switch adapted to shunt a portion of said rheostat, and a switch actuator including a portion extending between said hopper and chamber and into the path of ow of material from said hopper to said chamber.

10. A drier comprising a support, an open ended substantially upright chamber carried by said support, baffles within said chamber, means `for heating said chamber, a feed hopper carried by said support and discharging into said chamber, said hopper having a tapered lower discharge portion located adjacent the upper part of said chamber and of smaller cross-sectional size than the adjacent portion of said chamber, said sup port including a pair of spaced horizontal members positioned on opposite sides of said chamber, said chamber having a pair of opposed outwardly upwardly daring flanges at its upper end partially overlying said horizontal members to suspend said chamber therefrom, and retainers carried by said support and engaging said chamber flanges to restrain lateral and upward movement of said chamber relative to said support.

BUFORD R. SMITH.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 696,580 Mumford Apr. 1, 1902 735,878 Hutton Aug. 11, 1903 872,104 Bacon Nov. 26, 1907 1,574,210 Spaulding Feb. 23, 1926 2,069,193 Behr et al. Jan. 26, 1937 v FOREIGN PATENTS Number Country Date 349,308 Great Britain May 28, 1931 

